Field of the Invention
The present invention relates to lights and tracking systems for use in low light environments such as underground mines. More specifically, the present invention relates to lights using visible and ultraviolet light to illuminate unique markings associated with certain assets and a system for identifying and tracking those assets.
Description of the Related Art
Low light conditions present a hazard to underground mine workers and the like who work in close proximity to large industrial machinery. To increase visibility, such workers are often outfitted personal protective equipment such as reflective or high visibility colored clothing. The introduction of LED lighting technology has reduced much of the ultraviolet (UV) radiation emitted from an artificial light source to near zero. While the efficiency of the LED lighting is very desirable, its use alters the spectral breadth of the light being produced. The lack of ultraviolet light degrades the effectiveness of safety markings placed on equipment and the clothing and safety equipment worn by personnel, in that many of such markings are designed to fluoresce, which requires the presence of UV spectral power.
Ultraviolet light is an electromagnetic radiation with a wavelength from roughly 10 nm (30 PHz) to 380 nm (750 THz), which is a shorter wavelength than that of visible light but longer than X-rays. UV radiation is present in sunlight, and also produced by electric arcs and specialized lights such as mercury-vapor lamps, tanning lamps, and black lights. Although the UV light lacks the energy to ionize atoms, long-wavelength ultraviolet radiation can influence chemical reactions, and causes many substances to glow or fluoresce.
In certain situations, it is often advantageous to be able to identify certain objects and distinguish them from other objects in low light conditions. For example, different actions may need to be taken if an underground mining machine identifies a person in its field of view as opposed to another machine in that same field of view. It may also be beneficial to track assets that are identified as being in the proximity of a particular machine in an underground mine.
Accordingly, there is a need for a lighting unit for use in low light areas that emits visible light and ultraviolet light to improve the fluorescing of reflectors in low light conditions. There is also a need for a system using such a lighting unit that can identify and track objects in low light conditions and differentiate objects from other objects.